What a question, not as easy to answer as one may think, but let's try! It all depends on your interests and professional goals. Off the top of my head I can think of the following sciences that would apply to law enforcement:
Accounting/Finance: Are you familiar with the infamous Chicago mobster Al Capone? Do you know how they got him? It was the treasury department that got him for tax evasion. This is also one of the critical skills sought after by the FBI when recruiting special agents. However, if you're not into numbers and spreadsheets then this is also an area that will bore you to tears!
Chemistry/Physics/Engineering: These are components of physical sciences which, you guessed it, is another critical skill for the FBI. This is a position where you working either in a lab or at a crime scene. You could be analyzing a suspected narcotic to determine it's composition and weight, or you could be determining the angle in which a bullet penetrated an object or person. It's also a skill that helps when determining a motor vehicle collision. It's usually wise to continue your education in pursuit of a masters or PhD in this field, as that will open up greater career possibilities (and greater income potential).
Computer Science: You guessed it, another FBI critical skill! This is a highly sought after skill!!! You typically hear about this skill applied to the investigation of sex offenses. I can't tell you how many 40+ year old detectives I know who pose on Facebook as underage girls! These specialized detectives are also typically responsible for investigating child pornography cases - rather involved as you need to identify as many factors as possible about the picture and subject in the picture, identify the offender's IP address, obtain a search warrant to review all of the contents of their computer's hard drive/phone memory/digital cameras/etc...basically anything that has the ability to store data. This is also useful when investigating drug traffickers, terrorist activities, domestic violence, embezzlement (goes along with finances), or any other crime where a computer related device was used. There's several free courses available online to learn computer coding, and I would highly suggest starting with the best of the best (just copy and paste to your browser): https://openlearning.mit.edu/beyond-campus/mitx-edx-moocs/courses
Biology: This is part of the life sciences, and interestingly enough, not on the FBI's critical skill list. Expertise in this area is best applied with a position at a forensic lab with the State Police or Federal law enforcement. You would typically enter and compare DNA, test various bodily fluids and other crime scene items. This is also a skill that would help you get a job as a medical examiner (typically the one who determines the cause of an untimely death). Once again, masters or PhD (heck, even MD) for greater career and income potentials.
Psychology/Sociology: Also not on the FBI's critical skill list (though it doesn't mean they wouldn't consider someone with expertise in this field). When I went to college my initial major was Criminal Justice, by my sophomore year I decided to add psychology as a double major. When I got out of college, my first job was thanks to the psychology degree - though I did eventually land in law enforcement a couple years later. This is everything in life, the study of the human mind!!! How is this not a critical skill? This is an area used to determine the motive (the why), modus operandi (the how), and intent (the anticipated outcome). This is also an extremely beneficial skill working with specialized teams, such as a hostage negotiator. Even in the sentencing phase of an offender, expertise in psychology (and sociology as a minor) will help with the pre-sentence investigation to determine the risk posed by an offender based on their upbringing.
This is only a partial list. The FBI's critical skills list also includes foreign language proficiency, law (if you major in pre-law, it's best to continue your education by attending law school and earning your Juris Doctor [JD] degree. Remember, think of an area of study that you're interested in - that passion will help you become the best in the field (I always tell people - if it's not a job you're interested in, then why are you doing it? If it's not going to set you on your long term path, then find something that will). Also remember, sometimes (well....most times) you have to start at the bottom and work your way up - like what I did - I made sure that what ever job I had before working in law enforcement would give me the experience I needed to eventually get a job in law enforcement. Good luck!!!!
Gary recommends the following next steps:
- Remember to check out MIT's online learning site (being from Massachusetts I am a bit biased, and know that MIT is the best...much like the Patriots - GO PATS!!!!): https://openlearning.mit.edu/beyond-campus/mitx-edx-moocs/courses